程序包 ohos.utils

Provides common basic system utilities.

This package provides the following basic system utilities for you to improve service development efficiency:

• Parcel, Sequenceable, and PacMap, related to data serialization for communication between processes;
• Uri, related to URI parsing;
• Pair, LightweightMap, LightweightSet, PlainArray, PlainBooleanArray, PlainIntArray, and LongPlainArray,related to data containers.
• Ashmem, provides methods related to the Ashmem, including creating, closing, mapping, and unmapping the Ashmem, reading data from and writing data into the Ashmem, obtaining the Ashmem size, and setting protection for the Ashmem.

从以下版本开始:

1

接口概要

接口	说明
FileWatcher.EventHandler	Provides a handler for processing file events.
IOutput	Defines a unified data output interface for ohos.
Sequenceable	Writes objects of a class into and restores them from a Parcel during inter-process communication (IPC).
Sequenceable.Producer<T>	Creates a Sequenceable instance from a Parcel.

类概要

类	说明
Ashmem	Provides methods related to the anonymous shared memory (Ashmem), including creating, closing, mapping, and unmapping the Ashmem, reading data from and writing data into the Ashmem, obtaining the Ashmem size, and setting protection for the Ashmem.
BasePacMap	Stores and reads data of basic types.
CapabilityConstants	已过时。 As of release 5, replaced by SystemCapability
CommonPattern	Provides methods for obtaining regular expressions used to verify common patterns.
ConditionHelper	A helper class to use the Condition class built in the java.util.concurrent.locks package without processing Lock and java.lang.InterruptedException exceptions.
Dimension	An immutable class used to describe the height and width of a Dimension object.
FileWatcher	Provides the capability of monitoring status changes of a specified file directory.
FloatDimension	An immutable class used to describe the height and width of a floating-point number.
HalfFloat	Encapsulates data of the half-precision floating-point format.
IntArray	A collection class of int arrays.
IntentConstants	Defines the Intent-related constants used in the system, including the actions, entities, and flags contained in the intents passed to methods for starting an ability.
IntervalTimer	Provides a timer for task execution that lasts for a while and repeats at regular intervals.
LightweightMap<K,V>	Provides a container that implements the Map interfaces.
LightweightSet<E>	Provides a container that implements the Collection and Set interfaces.
LongPlainArray<E>	A basic collection class to store the data structures that use the primitive data type long as the key and any object as the value.
LruBuffer<K,V>	A cache class that uses the least recently used (LRU) algorithm to remove the least recently accessed values when the capacity is insufficient for storing new values.
ObjectAttribute<O,T>	An abstract class of object attributes.
PacMap	Provides Map objects that support Sequenceable operations and can be used to store and read key-value pairs in character string format.
Pair<F,S>	Provides a data container that saves any two objects as one object.
Parcel	A data object used for inter-process communication (IPC).
PersistablePacMap	Extends the BasePacMap class and permanently stores data using the JSON string representation.
PlainArray<E>	A basic collection class to store the data structures that use the primitive data type int as the key and any object as the value.
PlainBooleanArray	A basic collection class to store the data structures that use the primitive data type int as the key and boolean as the value.
PlainIntArray	A basic collection class to store the data structures that use the primitive data type int as the key and value.
PlainLongArray	A basic collection class to store the data structures that use the primitive data type int as the key and long as the value.
RationalNumber	An immutable class representing a rational number.
Scope<T extends Comparable<? super T>>	Describes the range of valid values for a field.
SequenceUuid	Encapsulates a universally unique identifier (UUID) object, so that a SequenceUuid object can be converted to a Parcel object and vice versa.
Stopwatch	Provides the stopwatch function to log execution of subtasks split from a main task and uses HiLog to save the records in debug-level logs.

异常错误概要

异常错误	说明
ParcelException	Describes an exception that may be thrown when operations are performed on Parcel objects.